Nested HVMF-1 DNA-PCR analysis of monkey lymphomas. Lanes 1 through 5 are samples of monkeys 4, 208, OD5, 8503, and S1, respectively. Furthermore, samples from a spontaneous nasal non-Hodgkin's B-cell lymphoma from uninfected monkey (lane 6), from SL-P1 and SL-691 cells (in vitro established Simian Lymphoblastoid cell lines; lane 7 and 8, respectively), and from HUT 78 human T-cell line (lane 9) were included as controls.